re: Ballard
I just saw a documentary on oceanography (within shows about Jules Verne). Ballard said:
I invited a scientist to dive with him aboard de Alvin to explore the hydrothermal sources. Once underneath, he invited the scientist to look through the window. He calls him again and notices the scientist was all the time looking at the TV screen where according to him, the view was much better than from the window....
From that moment on, Ballard didn't invite scientists to the deep anymore but instead, uses the ROV.